A large number of cartridge valves are found in the prior art. Some of these valves are reciprocal type valves for adjustment of volume. Other valves are mixing valves which mix a preset volume of hot and cold water together which leaves the fluid exiting the valve at a desired temperature. Further, other valves combine both functions being reciprocating valves and temperature adjustable valves.
Some of the aforementioned valves include a pressure balancing spool therein to compensate for a change in the pressure of either the hot or the cold water feed lines. This structure is known in the art and may be embodied in either a mixing valve, in a reciprocal valve, or in combinations thereof.
Examples of valves which are reciprocal and rotatable are found in U.S. Pat. No. Re. 25,920 to Moen, U.S. Pat. No. 4,330,011 Moen, U.S. Pat. No. 3,730,222 to Moen which patents describe various forms of cartridges which may be used with a single lever valve. Alternatively, U.S. Pat. No. 4,469,121 to Moen describes the use of a pressure balancing spool in a cycle valve which is non-reciprocating and has no provision for volume control.
U.S. Pat. No. 4,033,370 to Egli teaches a mixing valve for control of water temperature and pressure as well as the volume of the water discharged from the valve. A pressure balancing spool is incorporated with the valve which spool includes a rubber sleeve such as best seen in FIG. 4 which has fins and ribs which extend outwardly away from the spool portion and provide a seal against an adjacent surface.
U.S. Pat. No. 2,308,127 to Symmons describes a non-scald mixing valve which is reciprocal and also rotatable in a valve housing, and includes a pressure balancing member within a hollow in the center of the valve which compensates for the changes in pressure in either the hot or the cold water lines. U.S. Pat. No. 3,448,755 further describes a valve by Symmons with an improved volume control. U.S. Pat. Nos. 3,960,016 and 4,917,137 further describe improvements to his pressure balancing concept.
Alternative types of sealing have been provided for these cartridges in order to minimize the effect of the grit found in the hot water stream, in particular, which may cut the seal if the seal were left in the direct path of the water flow. U.S. Pat. No. 4,395,018 describes such a seal which seal is positioned on a sleeve out of the path of flow with the stem outlet port being closed by the seal member when the valve is in a closed position. The seal is a generally well known seal of the "O" Ring type.
Canadian Patent 1,052,229 to Moen describes a flexible rubber sleeve located between a movable valve member and a stationary sleeve, which rubber sleeve is positioned within the valve sleeve at a location to mask sleeve inlet ports 38 and 40 as described in the specification. This sleeve partially collapses in a operation which will permit water to flow toward the sleeve outlets. It is interesting to note that the outlets are actually beyond the flexible sleeve which is best seen in FIG. 3 of the figures thereof.
The following references describe a body sealing member which seals the inlet of the stationary sleeve in relation to the movable sleeve only. No discussion of sealing the outlet in these references is found. These references therefore are: U.S. Pat. No. 4,495,969 to Givler, U.S. Pat. No. 3,726,317 to Moen, U.S. Pat. No. 3,916,950 to Mongerson, U.S. Pat. No. 3,840,048 to Moen, Canadian Patent 943,523 to Mongerson and Moen. However, these references teach only a body portion forming a seal only at the inlet of the valve and nowhere is there described the advantages of sealing the outlet as well should the inlet seal of the body portion fail.
It is also known in the art to provide separate check valves upstream of a valve assembly to prevent the backflow of waste effluent through an outlet of a valve into a valve to contaminate the the fluid streams. The present invention provides a seal on the outlet of a valve assembly which also provides a check to prevent backflow of waste into the valve assembly.
Nowhere within the prior art is there found a cartridge for a kitchen, lavatory, or shower valve which cartridge may include a pressure balancing spool, an internal mixing chamber, or a separation of the water paths, all of which cartridges may be placed in a standardized housing. Should the user of the valve desire to replace a standard valve which has a mixing chamber therein with a pressure balancing spool contained within a similarly sized cartridge, he or she merely replaces the cartridge and the installation is complete. Therefore, there will be no requirement for removing the old housing and the necessary repairs to the adjacent area of the valve. Further this valve incorporates a unique seal unknown in the prior art which seal is formed as a body having sealing portions located adjacent both the inlet and the outlet of the valve so that should the inlet portion fail, the outlet portion will maintain a seal in the valve which also provides a check to prevent backflow of waste into the valve assembly.
It is therefore a primary object of this invention to provide a standardized cartridge for a valve housing which offers the advantage of replacing a valve cartridge of one function with a valve cartridge with enhanced functions.
It is a further object of this invention to provide a valve cartridge containing a unique seal which seals both the inlet and the outlet of the valve cartridge.
It is yet a further object of this invention to provide the structure of a unique seal which seals both the inlet and the outlet of a valve.
It is yet a further object of this invention to provide the structure of a unique seal which also provides a check to prevent backflow of waste into the valve assembly.
Further and other objects of this invention will become apparent to a man skilled in the art when considering the following summary of the invention and detailed description of the preferred embodiments of the invention illustrated herein.